19431-21-1Relevant articles and documents
Modelling of prebiotic synthesis and selection of peptides under isothermal conditions and thermal cycling mode
Demina,Kononikhin,Laptev,Khodonov,Nikolaev,Varfolomeev
, p. 422 - 441 (2013/06/27)
The model peptide synthesis from mixtures of amino acids was carried out under the thermal cycling and isothermal modes. The compositions of the obtained mixtures of products and the primary amino acid sequence of the synthesized peptides were determined by Fourier transform ion cyclotron resonance mass spectrometry and tandem mass spectrometry in combination with high-performance liquid chromatography with the application of de novo sequencing of the synthesized products. The processes of abiogenous synthesis of peptides were shown to occur under relatively mild temperature conditions and give a substantially less number of peptides as compared with the possible statistical set. The evolution of the system takes place in the process of the synthesis in solid phase with the disappearance of a series of the most unstable peptides. The selection process with the formation of complementary peptides takes place in peptide synthesis under the thermal cyclic mode.
Trypsin-catalyzed Oligomerization of L-Lysine Esters
Aso, Keiichi,Kodaka, Hiroaki
, p. 755 - 758 (2007/10/02)
The oligomerization of L-lysine esters with a free α-amino group was done using trypsin as a catalyst in aqueous media, and some reaction parameters were examined.The pH-dependence of the reaction suggested that aminolysis by the substrate species having non-protonated α- and ε-amino groups was a dominant factor governing the reaction progress.At the beginning of the reaction lysine oligomers containing up to 8 residues were observed, but much of the dimer was accumulated during prolonged incubation due to secondary hydrolysis of highly polymerized products.The reaction yield depends on the ratio of enzyme and substrate; an overall reaction yield higher than 70 percent was attained after 2 hr of reaction when 1,000 mM of L-lysine ethyl ester was treated with 200 μM of trypsin at pH 10.0.The oligomerization was apparently enhanced by an addition of NaCl and by using the longer alkyl esters.
